ks8701 Samsung Semiconductor, Inc., ks8701 Datasheet - Page 56

• Manufacturer Part Number: ks8701
• Description: Flextm Roaming Decoder Ii
• Manufacturer: Samsung Semiconductor, Inc.

KS8701
RECEIVER CONTROL
INTRODUCTION
up and shut down timing as well as all of the various settings on the control lines through configuration registers
on the KS8701. The configuration registers for most settings allow the host to configure what setting is applied to
the control lines. how long to apply the setting, and if the LOBAT input pin is polled before changing from the
setting. With this programmability, the KS8701 should be able to interface with many off-the-shelf receiver ICs.
When using the internal demodulator (i.e. when the IDE bit of the configuration packet is set), the S0 pin becomes
the input for the demodulator and the S0 register setting in the receiver control configuration packets controls the
tracking mode of the peak and valley detectors for the internal data slicer. When the S0 bit is set in a receiver
setting, the internal data slicer will be in fast track mode. When S0 bit is cleared in a receiver setting, the internal
data slicer will be in slow track mode. For details on the configuration of the receiver control settings, see
“Receiver Control Configuration Packets” on page 30.
RECEIVER SETTINGS AT RESET
is reset and until the corresponding FRS bit in the Receiver Line Control Packet is set or until the KS8701 is
turned on by setting the ON bit in the Control Packet. This allows the designer to force the receiver control lines to
the receiver off setting with external pull-up or pull-down resistors before the host can configure these settings in
the KS8701. When the KS8701 is turned on, the receiver control ports are driven to the settings configured by the
“Receiver Control Configuration Packets” on page 30 until the KS8701 is reset again.
AUTOMATIC RECEIVER WARM UP SEQUENCE
turns on the receiver, it starts the warm up sequence 160ms before it requires valid signals at the EXTS0 and
EXTS1 input pins. (or the equivalent internal signals when using the internal demodulator/data slicer). The first
step of the warm up sequence involves leaving the receiver control lines in the “Off” state for the amount of time
programmed for “Warm Up Off Time”. At the end of the “Warm Up Off Time”, the first warm up setting, if enabled,
is applied to the receiver control lines for the amount of time programmed for that setting. Each subsequent warm
up setting is applied to the receiver control lines for their corresponding time until a disabled warm up setting is
found. At the end of the last used warm up setting, the “1600sps Sync Setting” or the “3200sps Sync Setting” is
applied to the receiver control lines depending on the current state of the KS8701. The sum total of all of the used
warm up times and the “Warm Up Off Time” must not exceed 160ms. If it exceeds 160ms, the KS8701 will
execute the receiver shut down sequence at the end of the 160ms warm up period. The receiver warm up
sequence while decoding when all warm up settings are enabled is shown in figure 11 on page 56.
The KS8701 has 8 programmable receiver control lines (S0 - S7). The host has control of the receiver warm
The receiver control ports are three-state outputs which are set to the high-impedance state when the KS8701
The KS8701 allows for up to 6 steps associated with warming up the receiver. When the KS8701 automatically
APPENDIX A : APPLICATION NOTES
FLEX
TM
Roaming Decoder II
Appendix A: Application Notes
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